Help! Bell skiver problem: scrap deflector malfunction

[AlainaZ]

Greetings everyone,

We recently acquired a new DCS-S4 Consew bell skiver (It's possible it was refurbished. We purchased it from Consew itself).  It worked great for the first month, but for the last few months has been behaving badly and I can't find a way to fix it. I'm newish to skiver repair, though fairly experienced with industrial sewing machines. 

Here is what happens: after being skived off, the scrap somehow comes back up around the roller stone. The scrap seems to stick to it. This is with several types of leather, from buttery soft kid to crisp several-mm-thick laminated stuff used for a leather jacket. (forgive my lack of knowledge about leather types, it's not my area of expertise!)

I thought maybe the leather scrap deflector was bad in some way, so I moved it around, and even removed it to make sure the leather was not worn down all the way. I can't see anything obviously wrong. It is positioned firmly and fully against the stone. 

The "waste feeder metals" (Consew's part names are bizarre...it's the same part as 1.50 1105 in the DCS-S3 parts book*) is present. I don't know how it is SUPPOSED to be set, but It looks like it's in the right place to "scoop" the leather scraps out of the bell knife. It doesn't adequately clear the bell, I should note. I have to go in fairly often with tweezers to pull scraps out. 

I then thought maybe the stone had gotten sticky with leather residue so I cleaned it with a soft wire brush. No change.

So I'm out of ideas. Anyone have suggestions?? The image attached is from when I made the mistake of walking away from the student skiving, and this happened. 

Thanks for ANY suggestions. I'll take them all into consideration. 

-Alaina

* here is the parts book I'm referencing, since I can't find one for my precise model http://www.consew.com/Files/112347/PartsBooks/DCS-S3.pdf

 

[YinTx]

Check out @RockyAussie's posts on bell skivers.  Seems the best solution is a vacuum attachment to the discharge section that keeps the leather cleared and from being picked back up by the feed wheel.

YinTx

[jimi]

Hi There, maybe try a rubber feed wheel, that could help?

[AlainaZ]

1 hour ago, jimi said:

Hi There, maybe try a rubber feed wheel, that could help?

Good idea, thanks! I will try that

>>>>>Check out @RockyAussie's posts on bell skivers.  Seems the best solution is a vacuum attachment to the discharge section that keeps the leather cleared and from being picked back up by the feed wheel.

Another excellent idea, we will also do that!

Edited November 11, 2019 by AlainaZ

[RockyAussie]

A wire brush is not likely going to clean out any stick stuff that may be on your feed stone. Try rubbing a good bit of talcum powder onto some scrap leather and feed it through so that the powder beds into the stone pores. I find that it is common that dumb retailers and sometimes tanneries will stick hide size information on paper that is then sticky taped onto the back of the hide. Even when you are splitting hides it can stick and come back up and around and !!!!#### is the result. I cant help you as to whether the deflector is set up alright still as both mine have suction and don't need them things. Hope that helps.

 

[keithski122]

Check out this thread .On it I posted some pics I had found on instagram of a suction system.

https://leatherworker.net/forum/topic/86653-help-a-guy-out-with-his-new-skiving-machine/

 

[AlainaZ]

On 11/11/2019 at 5:57 AM, RockyAussie said:

A wire brush is not likely going to clean out any stick stuff that may be on your feed stone. Try rubbing a good bit of talcum powder onto some scrap leather and feed it through so that the powder beds into the stone pores. I find that it is common that dumb retailers and sometimes tanneries will stick hide size information on paper that is then sticky taped onto the back of the hide. Even when you are splitting hides it can stick and come back up and around and !!!!#### is the result. I cant help you as to whether the deflector is set up alright still as both mine have suction and don't need them things. Hope that helps.

 

Thanks for the advice, I'll give that a try. With 1000+ students using our machines, we never know what sticky messes they are putting through them. 

@RockyAussie, (or anyone else) one more question for you. I received a part that I didn't order...but now I'm wondering if I should keep it. The manual calls it a Knife Shaft lead pipe key (2.23 #1020). Is this a tool I might need? What does it do?

 

Edited November 18, 2019 by AlainaZ

[RockyAussie]

Highly unlikely you will ever need to need it. Time to replace the machine before that part would ever go.

[Mrvista]

you might find this useful, watched this on YouTube, it would seem that the bell is adjustable, as you sharpen the knife, the gap between the knife and the bell gets wider, the gap needs to be closed up, to ensure that the skived off leather is deflected away, and not pulled up around the feed roller. Don’t know if your model has this adjustment, but might be worth watching the video.

regards

Andy

Apricity Leatherworks.
 

https://youtu.be/8IHP9eHgHHA

[Lil Doodler]

Hi,

May I suggest . . . ?

According to a skiver trouble shooting chart I have,

it could be

a) The wheel is rotating too fast

b) Feeding roller's surface has bad quality

 

Also the "waste disposal plate" inside the bell knife might not be in the best place?

That's part #1 in the diagram you posted.

The "waste disposal plate" shouldn't be deep inside the bell knife, it shouldn't be too close to the stone feeding roller.

Over time, when you sharpen the bell knife many times, the side of the bell knife shortens

and the "waste disposal plate" will need to be re-positioned away from the stone feeding roller

 

Hope this helps!

 

Edited December 24, 2019 by Lil Doodler

[Bmwmoa67707]

My wife got a new Thor bell skiver about three years ago, and the same problem soon developed, the waste not getting scraped off the stone roller wheel....very puzzling....tinkered with it a lot before thinking that possibly there was simply not enough spring pressure on the scraper itself.  So I took the scraping assembly apart, wound the spring tighter, which created more pressure on the veg-tan piece of leather (scraping blade)  that actually does the scraping, and it has worked well for her since then.  I would guess that over time the veg-tan scraping "blade" will wear out and require replacement, not difficult to simply make one from a stiff piece of veg-tan from the scrap box. 

YMMV,

Steve

[keithski122]

Nice trouble shooting chart Lil Doodler.Have you got any other pages that may be useful?

[Lil Doodler]

Oops, I forgot . . .

Under the feeding roller/stone, there should be a scraper that prevents the scraps from coming getting stuck

just as Bmwmoa67707 suggested

[Lil Doodler]

Thanks Keithski122

Is there something you are looking for?

That chart came from this online manual. Lots of good information here

http://sunstarmexico.com/wp-content/uploads/2018/02/Manual-KM-76_MME.pdf

There's a guy with a lot of knowledge about upholstery tasks, and machinery (including skivers) on Youtube.

First video shows kind of how the skiver works, its parts, and how to replace them

Second video I think is dedicated to setting up the machine

Harry Rogers on Youtube has good information on various leather tasks, projects and equipment too

Edited December 26, 2019 by Lil Doodler

[blue duck]

@Lil Doodler Thank you so much for the manual! For whatever reason this seems to be a rare resource. Thankfully folks here have helped more than they know, but this can go right by the machine.

[keithski122]

Nothing in particular, I have the global version of this machine and had it set up by an engineer however I'm afraid to touch any setting on it now it works.Always nice to have as much information as possible.Mine has the scraper on it but the spring has come unattatched so I need to work out where it was fitted and refix it.Thanks for the manual, its far better than the one supplied with my machine.

Edited December 27, 2019 by keithski122